I was getting the error code on my Cherokee (1221). I changed the O2 sensor and the code cleared for about a week. Now it's back. Do I need to change the converter or is it something else?
- posted
19 years ago
Bad Catalytic Converter?
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19 years ago
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19 years ago
2 codes perhaps ?
12* Direct battery input to PCM was disconnected within the last 50 key-on cycles.
21** Neither rich nor lean condition detected from the oxygen sensor input. or Oxygen sensor input voltage maintained above the normal operating range.
Dave Milne, Scotland '91 Grand Wagoneer, '99 TJ
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19 years ago
Dave Milne did pass the time by typing:
Yep.
Double check the sensors. Most have one upstream of the cat but somewhere during the years they stuck one after the cat. Both can cause that error. Also check the harness at the front side of your engine by the motor mount. (might have to move the air box) Look to see if the harness got pinched and burned.
If it's before the cat then the cat can't be monitored and it's proably the wiring. 21 says the computer can't find the O2 sensor. I'd be checking the wiring harness all the way to the computer.